(This is my first post, but I've been reading the forums for a while.) We found all 15 of our broilers dead this evening. I think they died due to the heat, but I want to be sure there isn't a disease going around that we should worry about. We keep them in a Joel Salatin-style portable pen in the pasture. They had plenty of food and water. The pen is partially covered to provide shade and has lots of ventilation. We also had the pen in a spot that is shaded during the hot afternoon sun. It was in full sun during the early part of the day, but I thought that would be ok since it wasn't the worst heat of the day. HOWEVER, it did reach 107°F today. All of them were laying down with their feet under them as though they just went to sleep and never woke up. Oddly, we had another laying hen chick (i think its a maran, it was a mystery chick) in there with them because it's the same age, and it didn't die. It seems just fine. All of this is why I think it was the heat that killed them. The chick that lived is much smaller and not as susceptible to heat as the Cornish x breed. What do you think? We are about to go back out and re-inspect some of the bodies. What should we look for? We also have laying hens in the same pasture, so I don't want them to catch something contagious.